1. Field of the Invention
The present invention relates to medical procedures and instruments and, more particularly, to a universal handle providing a retracting and/or a protruding function for medical instruments.
2. Brief Description of the Related Art
Penetrating instruments are widely used in medical procedures to gain access to anatomical cavities ranging in size from the abdomen to small blood vessels, such as veins and arteries, epidural, pleural and subarachnoid spaces, heart ventricles and spinal and synovial cavities. Use of penetrating instruments has become an extremely popular and important first step in endoscopic, or minimally invasive, surgery to establish an endoscopic portal for many various procedures, such as laproscopic procedures in the abdominal cavity. Such penetrating instruments typically include a cannula or portal sleeve and a penetrating member disposed within the cannula and having a sharp tip for penetrating an anatomical cavity wall with the force required to penetrate the cavity wall being dependent upon the type and thickness of the tissue forming the cavity wall. Once the wall is penetrated, it is desirable to protect the sharp tip of the penetrating member from inadvertent contact with or injury to tissue or organ structures in or forming the cavity in that, once penetration is achieved, the lack of tissue resistance can result in the sharp tip traveling too far into the cavity and injuring adjacent tissue or organ structures.
Various safety penetrating instruments have been proposed, generally falling into protruding and retracting categories. In protruding safety penetrating instruments, a safety member is spring-biased to protrude beyond the tip of the penetrating member in response to the reduced force on the distal end of the safety member upon entering into the anatomical cavity. The safety member can be disposed around the penetrating member in which case the safety member is frequently referred to as a shield, or the safety member can be disposed within the penetrating member in which case the safety member is frequently referred to as a probe. In retracting safety penetrating instruments, the penetrating member is retracted into the cannula upon entry into the anatomical cavity in response to distal movement of a component of the safety penetrating instrument such as the penetrating member, the cannula, a probe or a safety member such as a shield or probe.
A disadvantage of safety penetrating instruments in general is that relatively complex mechanisms are required to retract a penetrating member or protrude a safety member such that integral construction of the safety penetrating instruments requires sterilization or disposal of the entire unit after use, significantly increasing the cost of utilizing such instruments. Another disadvantage of the prior art instruments is that penetrating components, such as the penetrating member and safety member, are not interchangeable between penetrating instruments. As such, if the type or size of a penetrating component is not correct for the application, an entirely new safety penetrating instrument must be selected. Moreover, there is no flexibility to selectively match a particular penetrating component with a particular protruding or retracting power.